CINCINNATI—Research that has involved thousands of Cincinnati-area residents over the past 16 years is assured of another five years of shedding light on stroke incidence and awareness.
The Greater Cincinnati/Northern Kentucky Stroke Study, which identifies all hospitalized and autopsied cases of stroke and transient ischemic attack (TIA) in a five-county region, began in 1993 at the University of Cincinnati (UC) College of Medicine. Since that time, at least 20,000 people have contributed to the understanding of stroke through the study.
Brett Kissela, MD, and Dawn Kleindorfer, MD, co-principal investigators for the project and associate professors in the neurology department, recently learned that they were successful in an application with the National Institutes of Health to renew the study for another five years. The total grant award is about $6.8 million.
“This grant will support a lot of people for a very large team,” says Kissela. “The study is such a great resource for understanding stroke—how it applies in our community and therefore how we can generalize that out to the rest of the country.”
Says Kleindorfer: “Any new drug, any new therapy, any clinical trial that’s going to be planned has to start with this question: How many people is it going to be relevant for? That’s where our study comes in.”
The Greater Cincinnati/Northern Kentucky Stroke Study was begun by Joseph Broderick, MD, its first principal investigator and now chair of the neurology department. He had spent five years as a medical intern, neurology resident and fellow in cerebrovascular disease at the Mayo Clinic in Rochester, Minn., where records about incidence of stroke over time had been kept in a central repository since the 1950s.
“When I came to Cincinnati, I thought it would be nice to do it in a population that’s more representative of the United States, because Rochester’s population was well to do, highly educated and pretty much all white,” says Broderick. “That way, the data from our population could be used to provide some of the best information on what’s happening in stroke in our country.”
As Kleindorfer puts it, “Anytime you hear the national numbers for stroke, they come from our city.”
In addition to screening all hospitals and coroner’s offices in the region, plus a sampling of nursing homes and physicians’ offices, study team members also conduct surveys of the general population to assess stroke awareness and understanding. “We’re trying to figure out what they know, what they understand and how that’s changing over time,” Kleindorfer says.
Over the past 16 years, the study has produced numerous major findings, particularly with regard to racial disparities in stroke. It found that African-Americans have higher rates of stroke than Caucasians, and that they tend to have them at a younger age. In addition, the study found that the number of hemorrhages due to blood thinners rose four-fold over a 10-year period due to increased use of blood thinners to prevent stroke due to atrial fibrillation.
“Nobody had known that before, and that’s why you have to track what happens over time to see how stroke is changing in the city by age, race and gender, and how our care is changing in the city,” says Broderick.
Earlier this year, Kleindorfer presented information at the International Stroke Conference in San Diego showing that ischemic stroke incidence (caused by blockage of blood flow to the brain) appears to be declining over time with whites while remaining stable among blacks, suggesting a possible racial disparity for black stroke incidence. That paper was selected among the top 5 percent of scientific presentations at the upcoming American Academy of Neurology meeting in Seattle, along with her poster on eligibility for the clot-busting drug rt-PA among ischemic stroke patients.